同质和异质无形金属相位形成和相位稳定性与晶体相位相比
Yidi Shen1,2, Konrad Samwer3,4, William L Johnson3
1Department of Materials Science and Engineering, Iowa State University, Ames, IA 50011.
概括
在金属玻璃中发现了两种不同的无形相,L相和G相. G相与脆化有关,在不同的热条件下可以转化为其他相.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 计算材料科学科学 计算材料科学
背景情况:
- 金属玻璃表现出复杂的无形结构.
- 了解金属玻璃的相变对于它们的应用至关重要.
研究的目的:
- 在金属玻璃中识别和描述不同的无形相.
- 为了研究无形和晶体状态之间的相变.
- 阐明无形相在材料特性如脆性中的作用.
主要方法:
- 分子动力学 (MD) 模拟融和热衰老.
- 分析两相平衡和晶体到玻璃的过渡.
- 缺陷积累效应的模拟,缺陷积累效应的模拟.
主要成果:
- 确定了两个无形相:同质的L相和异质的G相.
- 在不同温度下确定相变换路径.
- 链接G相存在于金属玻璃中的脆化.
- 经过证明的热层干扰驱动了晶体 (X),L和G相之间的过渡.
结论:
- G相是金属玻璃脆化的一个关键因素.
- 无热过程,如缺陷积累,可以诱导无形和晶体相之间的过渡.
- 不同的无形相表现出独特的行为和转化途径.
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